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Swift: Programmatically change size of a button in runtime

I use two buttons in a camera app to track the zoom of said camera. My goal is to reduce the height & width of 1x if 2x is selected and vice-versa but it doesn't seem to work.

I tried button.frame.size.height = 8 button.frame.size.width = 8 and the height & width always remain the same. I even tried 500 to see if it would make a difference and it didn't. I also tried button.size(CGFloat) to no avail...

I should probably mention that those buttons are nested in a StackView and the app is built on Storyboards. Also, the app is designed to be used on iOS 13+.

Thanks in advance!

Solution

  • UIStackView is using Auto Layout for arranging its subviews. Therefore, direct modifications of the button's frame will have no effect because Auto Layout will anyway recalculate all frames according to the active constraints on the next layout pass.

    Since you're using a storyboard, here's how to solve it:

    1. Open the storyboard, select your button and create a width and a height constraint for it.
    2. Create IBOutlets for each of these constraints in your view controller. For the sake of the example let's say you name it buttonWidthConstraint and buttonHeightConstraint.
    3. Whenever you want to change the size of the button, do this:
    buttonWidthConstraint.constant = 8
buttonHeightConstraint.constant = 8